This application relates to devices used in healthcare and, more particularly, to a system for illuminating a subject for diagnostic and treatment purposes. More particularly, the application relates to a system for illuminating portions of a dental patient's oral cavity during treatment procedures.
Conventional light sources used during dental procedures rely upon incandescent light sources such as halogen-based light bulbs or arc lamps such as xenon or mercury arc lamps. Light from the light source is transmitted via a fiber optic cable to a light wand or handpiece that may be inserted into a patient's oral cavity during treatment. Light exits a conventional light wand to illuminate the oral cavity during treatment. Typically, the light emanating from conventional sources has a color temperature of about 2800° K to 3500° K, which appears to have a yellowish color. The yellow color of the light emitted from incandescent sources does a poor job of making caries visible to the treating dentist. Caries often appears as a brownish discoloration on the enamel of a patient's tooth. When using an incandescent light source such as a halogen source, the brownish caries appears to be almost the same color as surrounding pale yellow healthy enamel.
Some conventional light sources used in dental procedures incorporate xenon vapor sources that have a much higher color temperature, typically about 6000° K Such sources generate a much whiter light. Xenon sources do a much better job than incandescent sources of making caries easily visible. The brownish color of caries appears much different from surrounding healthy enamel when the caries is illuminated with a xenon source.
However, both incandescent and xenon light sources generate extreme heat. Whenever one of these conventional light sources is coupled to a lighting handpiece via a fiber optic cable, the heat generated by the light source causes the optical fiber in the bundle to deteriorate. Over a relatively short time period, the fiber bundle loses its ability to transmit light resulting in the light emitted from the handpiece growing dimmer. In such systems, manufacturers typically suggest replacing the fiber optic bundle every 12 months. These fiber bundles are expensive and replacing the bundle renders the lighting system and therefore the workstation with which it is associated inoperative during the replacement procedure. The incandescent and xenon sources also consume a great deal of power, typically 250 W or more.
Other lighting handpieces incorporate light sources that are solid state devices such as light emitting diodes (LEDs). Light sources such as these are discussed, for example, in U.S. Pat. No. 5,908,295, which is incorporated in its entirety by this reference. However, these LED sources are typically placed in the handpiece. Moreover, only one LED is used as a light source. One LED alone, when connected to a light wand using an optical fiber, does not produce sufficient light to illuminate satisfactorily the patient's oral cavity.